Tanveer A Bhuiyan1, Claus Graff2, Jørgen K Kanters3,4, Jimmi Nielsen5,6, Jacob Melgaard2, Jørgen Matz7, Egon Toft2,8, Johannes J Struijk2. 1. Department of Health Science and Technology, Aalborg University, Frederik Bajers vej-7 C1, 9220, Aalborg, Denmark. tb@hst.aau.dk. 2. Department of Health Science and Technology, Aalborg University, Frederik Bajers vej-7 C1, 9220, Aalborg, Denmark. 3. Laboratory of Experimental Cardiology, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark. 4. Department of Cardiology, Herlev and Gentofte University Hospitals, Copenhagen, Denmark. 5. Department of Clinical Medicine, Aalborg University, Aalborg, Denmark. 6. Psychiatry, Aalborg University Hospital, Aalborg, Denmark. 7. Global Pharmacovigilance, H. Lundbeck A/S, Copenhagen, Denmark. 8. College of Medicine, Qatar University, Doha, Qatar.
Abstract
BACKGROUND AND OBJECTIVE: The T-peak to T-end (TpTe) interval has been suggested as an index of transmural dispersion and as a marker of drug-induced abnormal repolarization. In this study, we investigate the relation between TpTe and the QT interval. METHODS: Electrocardiograms (ECGs) from five different drugs (sotalol, sertindole, moxifloxacin, nalmefene, and Lu 38-135) and from a placebo group were analyzed. Semi-automatic measurements of T-peak, T-end, and QRS onset were obtained. The TpTe/QT ratio was calculated to investigate the proportional relationship of QT and TpTe. RESULTS: Although a significant increase of both TpTe and QT from baseline is apparent with QT-prolonging drugs, the TpTe/QT ratio remained the same at baseline and after drug administration, thus indicating that prolongation of TpTe is just a fractional part of total QT prolongation. In the presence of notched or flattened T-waves, the uncertainty associated with measurement of the TpTe interval increases. The errors in TpTe for individual subjects may be substantial, thus complicating the use of TpTe for follow-up of individuals. CONCLUSIONS: The duration of the QT interval and TpTe are closely related. Drugs appear to prolong the TpTe interval as a predictable fraction of the total QT prolongation.
BACKGROUND AND OBJECTIVE: The T-peak to T-end (TpTe) interval has been suggested as an index of transmural dispersion and as a marker of drug-induced abnormal repolarization. In this study, we investigate the relation between TpTe and the QT interval. METHODS: Electrocardiograms (ECGs) from five different drugs (sotalol, sertindole, moxifloxacin, nalmefene, and Lu 38-135) and from a placebo group were analyzed. Semi-automatic measurements of T-peak, T-end, and QRS onset were obtained. The TpTe/QT ratio was calculated to investigate the proportional relationship of QT and TpTe. RESULTS: Although a significant increase of both TpTe and QT from baseline is apparent with QT-prolonging drugs, the TpTe/QT ratio remained the same at baseline and after drug administration, thus indicating that prolongation of TpTe is just a fractional part of total QT prolongation. In the presence of notched or flattened T-waves, the uncertainty associated with measurement of the TpTe interval increases. The errors in TpTe for individual subjects may be substantial, thus complicating the use of TpTe for follow-up of individuals. CONCLUSIONS: The duration of the QT interval and TpTe are closely related. Drugs appear to prolong the TpTe interval as a predictable fraction of the total QT prolongation.
Authors: Claus Graff; Jørgen Matz; Ellen B Christensen; Mads P Andersen; Jørgen K Kanters; Egon Toft; Steen Pehrson; Thomas B Hardahl; Jimmi Nielsen; Johannes J Struijk Journal: J Clin Pharmacol Date: 2009-11 Impact factor: 3.126
Authors: J J Struijk; J K Kanters; M P Andersen; T Hardahl; C Graff; M Christiansen; E Toft Journal: Med Biol Eng Comput Date: 2006-06-03 Impact factor: 2.602
Authors: Jørgen Matz; Claus Graff; Petri J Vainio; Antero Kallio; Astrid Maria Højer; Johannes J Struijk; Jørgen K Kanters; Mads P Andersen; Egon Toft Journal: Clin Drug Investig Date: 2011-11-01 Impact factor: 2.859
Authors: J Nielsen; M P Andersen; C Graff; J K Kanters; T Hardahl; J Dybbro; J J Struijk; J M Meyer; E Toft Journal: Acta Psychiatr Scand Date: 2010-01-19 Impact factor: 6.392
Authors: Jimmi Nielsen; Claus Graff; Thomas Hardahl; Mads P Andersen; Jens Kristoffersen; Johannes J Struijk; Egon Toft; Jonathan M Meyer Journal: Eur Neuropsychopharmacol Date: 2009-05-19 Impact factor: 4.600
Authors: Keith A Marill; Pat Dorsey; Anthony Holmes; Ketaki Muthal; Emily S Miller; Joel Xue Journal: Ann Noninvasive Electrocardiol Date: 2017-12-02 Impact factor: 1.468
Authors: Cao Thach Tran; Tania Atanasovska; Claus Graff; Jacob Melgaard; Jørgen K Kanters; Robert Smith; Aaron C Petersen; Keld P Kjeldsen; Michael J McKenna Journal: Eur J Appl Physiol Date: 2022-01-20 Impact factor: 3.078